hardbuprenorphinepartial agonistceiling effectmu-opioid receptorrespiratory depressionopioid use disordermedication-assisted treatment
A 35-year-old female with opioid use disorder is being transitioned from methadone 40 mg daily to buprenorphine/naloxone for medication-assisted treatment. During patient education, she asks why buprenorphine is considered safer than methadone regarding respiratory depression risk. The PMHNP explains the pharmacologic basis for buprenorphine's safety profile. Which of the following best describes the receptor-level mechanism responsible for buprenorphine's ceiling effect on respiratory depression?